Interior Paint Problems: Mold & Mildew

Mildew and mold can appear on the surface of paint or caulk as black, gray, green or brown spots.

Mildew is the visible sign of mold. Mildew build-up can occur on many surfaces, including painted ones. Never paint or caulk over mold or mildew; it must first be removed.

How to Identify Mildew

Mold and mildew thrive in warm, damp, or humid areas that receive little or no air circulation, areas that have high condensation, and areas that get little direct sunlight, such as bathrooms, kitchens, laundry rooms, and basements.

Test for mildew by applying a few drops of household bleach to the discolored area. If the discolorations disappear, they are probably mildew.

How to Prevent & Fix Mildew Problems

Properly prime the surface before painting

Use a high-quality latex paint. Consider using a mildew-resistant paint, such as Benjamin Moore's low-VOC Aura® Bath and Spa paint paint or Eco Spec® WB Silver, a zero-VOC commercial paint. Both are a low-odor interior paint containing additives to inhibit mildew growth on the paint's surface.

Take steps to reduce the humidity and increase air circulation in the room

If mildew already exists, scrub the surface with one part household bleach and three parts water. Wait 10 minutes, then rinse the area with water. Let the area dry thoroughly. If necessary, repeat the procedure until all traces of mildew are gone.